Journal of Experimental Psychology. Animal Behavior Processes

In each of three experiments, a single group of participants received a sequence of trials involving pictures of a variety of foods presented individually or in pairs. Participants were required to predict in which trials the food would lead to a hypothetical allergic reaction. The different trials involved blocking, A+ AX+, and a simple discrimination, BY- CY+, in which each letter stands for a different food. Training trials were followed by a test in which participants were asked to predict how likely each kind of food would be followed by the allergic reaction...

Two experiments used a novel, open-ended, and adaptive test procedure to examine visual cognition in animals. Using a genetic algorithm, a pigeon was tested repeatedly from a variety of different initial conditions for its solution to an intermediate brightness search task. On each trial, the animal had to accurately locate and peck a target element of intermediate brightness from among a variable number of surrounding darker and lighter distractor elements. Displays were generated from 6 parametric variables, or genes (distractor number, element size, shape, spacing, target brightness, and distractor brightness)...

Detecting change is vital to both human and nonhuman animals' interactions with the environment. Using the go/no-go dynamic change detection task, we examined the capacity of four pigeons to detect changes in brightness of an area on a computer display. In contrast to our prior research, we reversed the response contingencies so that the animals had to actively inhibit pecking upon detecting change in brightness rather than its constancy. Testing eight rates of change revealed that this direct report change detection contingency produced results equivalent to the earlier indirect procedure...

Two experiments demonstrated renewal effects in interference between outcomes in human participants. Experiment 1 revealed a XYX renewal effect, whereas Experiment 2 showed a XYZ renewal effect. The results from both experiments conformed to Bouton's (1993) theory of interference and recovery from interference, and contradicted the predictions derived from alternative accounts. Unlike previous demonstration of renewal effects, a cued response reaction time (RT) task was used, able to detect the effects of fast retrieval processes based on associative activation and that allowed little impact of inferential reasoning...

Pigeons were trained to discriminate photographs of cat faces from dog faces. They were then presented with test stimuli involving high- and low-pass spatial frequency filtering. Discrimination was maintained with both types of filtered stimuli, though it was increasingly impaired the more information was filtered out, and high-pass filtering impaired discrimination more than low-pass filtering. The pigeons were then exposed to hybrid stimuli in which high-pass filtered dog faces were combined with low-pass filtered cat faces, and vice versa...

Environment size has been shown to influence the reliance on local and global geometric cues during reorientation. Unless changes in environment size are produced by manipulating length and width proportionally, changes in environment size are confounded by the amount of the environment that is visible from a single vantage point. Yet, the influence of the amount of the environment that is visible from any single vantage point on the use of local and global geometric cues remains unknown. We manipulated the amount of an environment that was visually available to participants by manipulating field of view (FOV) in a virtual environment orientation task...

Two appetitive conditioning experiments with rats investigated the mechanisms and properties of unblocking that results from the surprising omission of an expected post-trial unconditioned stimulus (US). Experiment 1 demonstrated unblocking under circumstances in which differences in the contribution of generalization decrement and within-compound associations are equated across experimental and control groups. Following Stage 1 training in which a conditioned stimulus (CS) A was followed by a US and a post-trial US, in Experiment 2 we arranged for the post-trial US to be present on some trials with AX but not others...

The ability of rats to solve a discrimination between two objects that differ in length was investigated in five experiments. Using a rectangular swimming pool, Experiment 1 revealed it is easier to locate a submerged platform when it is near the center of a long rather than a short wall. For Experiments 2-4, the objects were black or white panels pasted onto the gray walls of a square pool, with two long panels pasted to two opposing walls and two short panels pasted to the remaining walls. The platform was easier to locate when it was placed near the middle of a long rather than a short panel...

Two groups of pigeons were trained to respond on a white center key to a fixed-interval, 60-s schedule of reinforcement signaled by the onset of a side-key cue (S+ training). In additional training sessions, S+ trials alternated between S- trials in which a different side-key cue signaled nonreinforcement after 60 s (S+/S- training). For one group, S+/S- training sessions followed S+ training, and for the other group, S+/S- training preceded S+ training. Peak-time curves obtained from extended nonrewarded probe trials inserted among training trials showed loss of control by time during S+/S- training relative to S+ training...

Miller and Shettleworth (2007) used an associative model of instrumental choice to explain a confusing pattern of results in the geometry learning literature. Dupuis and Dawson (in press) identified a structural flaw in the Miller-Shettleworth (MS) model and suggested replacing it with an operant perceptron model which can correctly reproduce some experimental results that the MS model does not. Here we demonstrate that the error in the MS model can be easily corrected without altering any of the model's predictions by making it stochastic rather than deterministic...

Three experiments used an ABA renewal paradigm to study deepening of response loss produced by extinction of reinstated or ABC renewed fear responses. In Experiment 1, rats were trained with two stimuli, S1 and S2, in context A and extinguished to S1 in context B and S2 in context C, shocked in B but not in C, and subjected to additional extinction of S1 in B and S2 in C. Rats froze less to S1 than S2 when subsequently tested in A. In Experiments 2 and 3, following training of S1 and S2 in A, one group received extinction of S1 in B and S2 in C followed by extinction of S1 in C and S2 in B...

Blocking of learning about a conditioned stimulus (the "blocked" cue) occurs when it is trained alongside an additional stimulus (the "blocking" cue) that has been previously presented with the outcome. A number of theories (e.g., N. J. Mackintosh. 1975a. A Theory of Attention: Variations in the Associability of Stimuli With Reinforcement. Psychological Review, 82, 276-298; J. M. Pearce & G. Hall. 1980. A Model for Pavlovian Learning: Variation in the Effectiveness of Conditioned But Not Unconditioned Stimuli...

A recent associative model (Miller, N.Y., & Shettleworth, S.J., 2007. Learning about environmental geometry: An associative model. Journal of Experimental Psychology: Animal Behavior Processes B, 33, 191-212) is an influential mathematical account of how agents behave when reorienting to previously learned locations in spatial arenas. However, it is mathematically and empirically flawed. The current article explores these flaws, including its inability to properly predict geometric superconditioning. We trace the flaws to the model's mathematical structure and how it handles inhibition...

In four experiments rats were conditioned to an auditory conditioned stimulus (conditioned stimulus; CS) that was paired with food, and learning about the CS was compared across two conditions in which the mean duration of the CS was equated. In one, the CS was of a single, fixed duration on every trial, and in the other the CS duration was drawn from an exponential distribution, and hence changed from trial to trial. Higher rates of conditioned responding to the fixed than to the variable stimulus were observed, in both between- (Experiment 1) and within-subject designs (Experiments 2 and 3)...

In three experiments, rats were trained to locate a submerged platform in one of the base corners of a triangular arena above each of which was suspended one of two distinctive landmarks. In Experiment 1, it was established that these landmarks differed in their salience by the differential control they gained over behavior after training in compound with geometric cues. In Experiment 2, it was shown that locating the platform beneath the less salient landmark potentiated learning based on geometry compared with control rats for which landmarks provided ambiguous information about the location of the platform...

Two experiments explored whether forgetting of an association depended on previous extinction of a different association in rats. Experiment 1 found that when rats were conditioned and extinguished with flavor X, a subsequently acquired conditioned aversion to flavor Y was reduced by a 19-day retention interval, something that did not occur when X and the US were initially presented unpaired. Experiment 2 found that when rats received training and extinction in one of two tasks (conditioned aversion to sucrose in Experiment 2a, and running for water in a straight alley in Experiment 2b), subsequent learning of the alternative task was partially forgotten over the 19-day retention interval...

Four experiments with rats examined renewal of extinguished instrumental behavior when the reinforcement histories of the contexts were equated by giving complementary training and extinction of a different response (lever press and chain pull) in each context. In Experiments 1 through 3, renewal occurred when the response was tested in the acquisition context (ABA) or outside the extinction context (AAB and ABC). Further, in Experiments 1 through 3, when both responses were simultaneously available, there was a clear preference for the response that was not in its extinction context...

Conditioned taste aversion (CTA) is traditionally viewed as an instance of pavlovian conditioning. This interpretation rests on the lack of an instrumental contingency between the tastant and the gastric malaise in a standard procedure of CTA. To investigate a role for instrumental punishment in CTA, we present 2 tastants sequentially ("sucrose then NaCl" or "NaCl then sucrose") in a daily alternating and counterbalanced order to rats with an explicit positive contingency between the dosage of the lithium chloride (LiCl) administered and the amount of 1 tastant drunk on that trial...

To determine what factors are important for minimizing interference effects in spatial memory, Clark's Nutcrackers, Nucifraga columbiana were tested for their spatial memory for two serial lists of locations per day. In this experiment two unique landmark sets were either different between List 1 and List 2 or the same. We found that Nutcrackers were most susceptible to interference when the landmark sets were the same. This study suggests that repeatedly testing animal memory in the same room, with the same cues, can hamper recall due to interference...

Previous research has demonstrated that nontool-using primates are capable of sophisticated motor planning for a single action. The present study extends this work by asking whether monkeys are capable of planning a sequence of repetitive motor actions to accommodate a task demand. We presented tamarins with a tape measure baited with a food reward at near or far distances and measured their manual intergrasp distances as they reeled in the food. In Condition 1, subjects viewed the reward as they pulled, whereas in Condition 2, they received no visual feedback during pulling...